Antonina Yermokhina, 86, does physical exercises during her daily training session on the embankment of the Yenisei River in the Siberian town of Divnogorsk, Russia November 13, 2017. (Photo by Ilya Naymushin/Reuters)

A woman greets a street artist at the San Fermin festival in Pamplona, northern Spain July 8, 2016. (Photo by Eloy Alonso/Reuters)

A man assist trucks carry palm oil fruit on a damaged road at Mesuji Raya village in Ogan Komering Ilir, South Sumatra province, Indonesia, January 11, 2017. (Photo by Budi Candra Setya/Reuters/Antara Foto)

A body of a victim lies trapped in the debris after an earthquake hit, in Kathmandu, Nepal April 25, 2015. Rescue efforts in Nepal are intensifying after nearly 2,000 people were killed on Saturday in the worst earthquake there in more than 80 years. Many countries and charities have offered aid to deal with the disaster. Seventeen people have been killed on Mount Everest by avalanches – the mountain's worst-ever disaster. Meanwhile a powerful aftershock was felt on Sunday in Nepal, India and Bangladesh, and more avalanches were reported near Everest. (Photo by Navesh Chitrakar/Reuters)

Indonesian rescuers search for victims of the crashed military airplane in Medan, North Sumatra, Indonesia, 30 June 2015. At least people 49 people were killed after an Indonesian military plane crashed in North Sumatra and burst into flames, officials said. Air Force chief Air Marshal Agus Supriatna said there were no survivors after the plane ploughed into houses and commercial buildings in Medan, the country's third largest city. The plane left Jakarta with 113 people aboard, including military personnel and their relatives, but it was not clear how many continued the journey to Medan after stopovers in Pekanbaru and Dumai, Agus said. (Photo by Dedi Sahputra/EPA)

Bottlenose dolphins swim over visitors in water tank at the Hakkeijima Sea Paradise aquarium-amusement park complex in Yokohama, southwest of Tokyo, Tuesday, July 21, 2015. Temperatures in Tokyo's metropolitan area neared around 96 degree Fahrenheit, or 35 degree Celsius, on Tuesday. (Photo by Shuji Kajiyama/AP Photo)

The 26th annual Visa Pour l’Image, the “Cannes Film Festival” of photojournalism kicks off, filling the French city of Perpignan with more than 3,000 of the world’s best photojournalists and photo editors, along with agencies from around the world. This year’s Visa Pour l’Image showcases 26 exhibitions around the city. Photo: Christians looting a Muslim shop in the “Combattants” district of Bangui. (Photo by Pierre Terdjman/Paris Match)

Wedges of an orange generate enough current and electrical juice – 3.5 volts – to power an LED. The fruit’s citric acid helps electrons flow from galvanized nails to copper wire in this 14-hour exposure. This image was published in September’s Visions of Earth, a trio of photos that appear in each issue of National Geographic. (Photo by Caleb Charland/National Geographic)